The present invention relates to apparatus and method for quickly and efficiently manipulating crossover tubes of a gas turbine. Crossover tubes are also known in this art as “crossflame” tubes.
In a gas turbine, there are a number of crossover tubes that communicate gas between the combustors (also referred to a burner baskets) of the gas turbine. A crossover tube is generally supported on the flange of a burner basket. In a 501 B&D Westinghouse gas turbine, there may be 30 crossover tubes between the burner baskets.
It is necessary to reach into the confines of the gas turbine, to handle the crossover tubes, in order to change the crossover tubes. Such handling requires that an operator reach into the confines of the gas turbine, to release the crossover tubes from their support on the burner baskets, and withdraw the crossover tubes from the turbine. In order to reinsert a new crossover tube, the tube must be manipulated to locate it in an appropriate position on a burner basket, and then lock it to the burner basket.
In the applicant's experience, handling such crossover tubes is a time consuming process that is often subject to “hit and miss” situations, in the sense that the existing tools known to applicant may or may not be capable of effectively engaging a crossover tube. Specifically, existing tools may or may not effectively engage the crossover tube, or may slip off the crossover tube, so that it may take an operator a number of tries to effectively engage a crossover tube, and then manipulate the crossover tube. In applicant's experience, it may take hours to engage and manipulate the 30 tubes of a gas turbine.
Also, there are generally a few crossover tubes that are particularly difficult to effectively reach, engage and manipulate. Specifically, a 501 B & D Westinghouse gas turbine generally has a manhole like cover that is removed in order to provide access to the burner baskets and crossover tubes. When the cover is removed, it is necessary for an operator to reach into the confines of the gas turbine with a tool, in order to remove at least 4 of the crossover tubes. Then, the operator can maneuver himself/herself through the opening and into the confines of the gas turbine, where it is a little easier for an operator to engage a crossover tube with a tool. Thus, the 4 or so crossover tubes that have to be removed by the operator with a tool, before the operator can maneuver into the confines of the gas turbine to remove the other crossover tubes, are particularly challenging.
Applicant believes there is a need for a. tool that can effectively and efficiently engage and manipulate a crossover tube of a gas turbine, in a relatively short time period. Moreover, there is a need for a tool that can effectively engage and manipulate those crossover tubes that are particularly difficult to handle.